When "Warehouse 13" returns Monday night (April 29) for Season 4.5, the ten-episode run will begin with the agents racing to save the world from the deadly "Sweating Sickness" that Artie (Saul Rubinek), having gone mad, unleashed using the Black Orchid Artifact. But, as executive producer Jack Kenny teased at NBC Universal's Summer Press Day on April 22, the season quickly turns very personal for Myka (Joanne Kelly)."Myka goes through a very big, life-changing event in Episode 7," Kenny told reporters. "She and Pete (Eddie McClintock) have to deal with that. It's very emotional. They keep it to themselves, and that also explodes into the finale, and it drives that a lot."While Kenny kept mum on details surrounding the event, he took the time to praise the work Kelly and McClintock do this season. "And honestly, these two, the relationship that is growing and changing," he said."They did some work in the last four episodes...